Allergy to Stinging Insects Can Be Life-Threatening

When warmer weather arrives, it is time to think about the return of stinging insects. About 3 percent of adult Americans are allergic to stinging insects. While the severity of these allergic reactions varies greatly, they cause at least 40 deaths each year in the U.S. alone.

Stinging insects belong to the class Hymenoptera and include bees, hornets, yellow jackets, wasps, and fire ants. Fire ants, which inflict a painful sting that belies their small size, are most common in the U.S. in the southeastern states, but they may have been introduced to other geographic areas throughout the country. All of the other stinging insects are found throughout the U.S. and Canada.

Most insect stings do not cause an allergic reaction, but simply result in pain, itching, redness, and swelling at the site of the sting. Cleaning the area and application of ice packs to reduce swelling are often the only treatment needed.

Most people who do have an allergy to stinging insects have mild reactions, such as extension of the area of swelling around the sting. In a more serious reaction, a person develops hives and itching all over the body.

The most dangerous allergic response to stinging insects is known as an anaphylactic reaction. Signs of an anaphylactic reaction include

An anaphylactic reaction usually occurs within minutes of a sting but may occur up to 24 hours afterward.

Prompt treatment of an anaphylactic reaction is of critical importance, since anaphylactic reactions can be fatal. The main treatment is with epinephrine, which is available (by prescription) in a self-injectable device that delivers the drug under the skin or into muscle. (Epi-Pen is an example of one brand of self-injectable epinephrine.)

People who are allergic to insect stings should carry injectable epinephrine at all times. This is most critical when medical attention is not readily available, such as on a hiking trip. Oral antihistamines (such as diphenhydramine [Benadryl]) can also be helpful for severe reactions, but these may take a half hour or more to take effect. Antihistamines should not take the place of epinephrine, but should be used in addition to epinephrine for sever reactions.

People who experience a severe allergic reaction to an insect sting should see a doctor right away, even if the reaction has been successfully treated, because further treatment may be needed later if the reaction recurs and progresses. Another reason to see a doctor is that after an allergic reaction, subsequent reactions can be even worse.

Of course, the first step in management of insect sting allergies is prevention. Try to avoid areas where there is an increased risk of stings, such as around insect nests and garbage cans. You should not walk barefoot outdoors.

An evaluation by an allergy specialist can determine whether allergy shots (venom immunotherapy) would be beneficial. Allergy shots are usually given twice a week for some months, with boosters every several weeks thereafter for approximately five years. The injections deliver increasing doses of the insect venom over time with the goal of decreasing the immune response to the agent. In most people who have taken the shots, their reactions to insect stings become much less severe. This treatment is safe and has a very low risk of adverse side effects.

For more information, please visit our First Aid Center.

Medically reviewed by Michael Manning, MD; American Board of Allergy & Immunology REFERENCE:

"Bee, yellow jacket, wasp, and other Hymenoptera stings: Reaction types and acute management"